================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline] BUG: KASAN: use-after-free in __mutex_lock+0x56e/0xaf0 kernel/locking/mutex.c:747 Read of size 8 at addr ffff88807826e108 by task jfsCommit/107 CPU: 0 PID: 107 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common kernel/locking/mutex.c:681 [inline] __mutex_lock+0x56e/0xaf0 kernel/locking/mutex.c:747 jfs_syncpt+0x21/0x90 fs/jfs/jfs_logmgr.c:1039 txEnd+0x2e1/0x520 fs/jfs/jfs_txnmgr.c:549 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline] jfs_lazycommit+0x5a2/0xa50 fs/jfs/jfs_txnmgr.c:2732 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 9851: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline] lmLogOpen+0x2c0/0xf90 fs/jfs/jfs_logmgr.c:1069 jfs_mount_rw+0xf2/0x5c0 fs/jfs/jfs_mount.c:253 jfs_fill_super+0x58e/0xac0 fs/jfs/super.c:565 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3069 do_mount fs/namespace.c:3412 [inline] __do_sys_mount fs/namespace.c:3620 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3597 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 4276: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 lmLogClose+0x293/0x520 fs/jfs/jfs_logmgr.c:-1 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88807826e000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 264 bytes inside of 1024-byte region [ffff88807826e000, ffff88807826e400) The buggy address belongs to the physical page: page:ffffea0001e09a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888078268000 pfn:0x78268 head:ffffea0001e09a00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001d59608 ffffea00013baa08 ffff888017441dc0 raw: ffff888078268000 000000000010000e 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 62, tgid 62 (kworker/u4:4), ts 77990411551, free_ts 77935597554 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node_track_caller+0x9e/0x230 mm/slab_common.c:956 kmalloc_reserve net/core/skbuff.c:446 [inline] __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515 alloc_skb include/linux/skbuff.h:1271 [inline] nlmsg_new include/net/netlink.h:991 [inline] br_info_notify+0x101/0x240 net/bridge/br_netlink.c:631 br_port_carrier_check+0x2f0/0x3d0 net/bridge/br_if.c:89 br_device_event+0x4af/0x880 net/bridge/br.c:89 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 netdev_state_change+0xd2/0x140 net/core/dev.c:1390 linkwatch_do_dev+0x10d/0x160 net/core/link_watch.c:168 __linkwatch_run_queue+0x408/0x660 net/core/link_watch.c:221 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x123/0x2f0 mm/slub.c:3383 kmem_cache_zalloc include/linux/slab.h:689 [inline] lsm_inode_alloc security/security.c:596 [inline] security_inode_alloc+0x30/0x110 security/security.c:1040 inode_init_always+0x8f8/0xc90 fs/inode.c:232 alloc_inode fs/inode.c:268 [inline] new_inode_pseudo+0x91/0x1c0 fs/inode.c:1063 new_inode+0x25/0x1c0 fs/inode.c:1091 debugfs_get_inode fs/debugfs/inode.c:72 [inline] __debugfs_create_file+0x148/0x510 fs/debugfs/inode.c:432 nsim_bpf_init+0x12f/0x250 drivers/net/netdevsim/bpf.c:635 nsim_init_netdevsim drivers/net/netdevsim/netdev.c:311 [inline] nsim_create+0x325/0x410 drivers/net/netdevsim/netdev.c:365 __nsim_dev_port_add+0x695/0xaf0 drivers/net/netdevsim/dev.c:1396 nsim_dev_port_add_all+0x35/0xe0 drivers/net/netdevsim/dev.c:1454 Memory state around the buggy address: ffff88807826e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807826e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807826e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807826e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807826e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================